#!/usr/bin/env python3
"""
Assemble a Roux issue's Hugo page bundles from a prompts JSON file.

  python3 scripts/build-issue.py --issue 02 --prompts data/prompts/issue-02.json

Reads an array of objects with keys:
  slug, title, description, category, tags[], prompt, featured (optional bool)

Writes content/posts/<issue>/<slug>/index.md for each, with plate numbers assigned
by stable sort on slug (matches scripts/import-posts.py). Frontmatter shape mirrors
the existing issue-01 bundles. `featured` comes from the JSON, so re-runs never lose
the homepage flags (unlike issue 01's hand-added ones).

Images are expected at content/posts/<issue>/<slug>/<slug>.png (written there by
scripts/generate-images.py). Pass --images DIR to copy them in from a staging dir
that holds either <slug>.png or <slug>/<slug>.png.
"""
import argparse
import json
import shutil
from pathlib import Path

SITE = Path(__file__).resolve().parent.parent


def norm_desc(desc: str) -> str:
    desc = desc.strip()
    if desc:
        desc = desc[0].upper() + desc[1:]
        if not desc.endswith((".", "!", "?")):
            desc += "."
    return desc.replace('"', '\\"')


def main() -> int:
    ap = argparse.ArgumentParser()
    ap.add_argument("--issue", required=True)
    ap.add_argument("--prompts", required=True, type=Path)
    ap.add_argument("--images", type=Path, help="staging dir to copy <slug>.png from")
    args = ap.parse_args()

    content = SITE / "content" / "posts" / args.issue
    content.mkdir(parents=True, exist_ok=True)

    entries = json.loads(args.prompts.read_text(encoding="utf-8"))
    entries.sort(key=lambda e: e["slug"])

    missing_img = []
    for idx, entry in enumerate(entries, start=1):
        slug = entry["slug"]
        plate = f"{idx:03d}"
        title = entry["title"].strip().replace('"', '\\"')
        desc = norm_desc(entry["description"])
        cat = (entry.get("category") or "Uncategorised").strip()
        tags = [t.strip() for t in entry.get("tags", []) if t.strip()]

        bundle = content / slug
        bundle.mkdir(exist_ok=True)
        img_name = f"{slug}.png"
        dst_img = bundle / img_name

        if args.images and not dst_img.exists():
            for cand in (args.images / img_name, args.images / slug / img_name):
                if cand.is_file():
                    shutil.copy2(cand, dst_img)
                    break
        if not dst_img.exists():
            missing_img.append(slug)

        cats_yaml = f'  - "{cat}"'
        tags_yaml = "\n".join(f'  - "{t}"' for t in tags) if tags else "  []"
        featured_yaml = "\nfeatured: true" if entry.get("featured") else ""

        md = f"""---
title: "{title}"
description: "{desc}"
plate: "{plate}"
slug: "{slug}"
issues:
  - "{args.issue}"
image: "{img_name}"
weight: {idx}{featured_yaml}
categories:
{cats_yaml}
tags:
{tags_yaml}
---
"""
        (bundle / "index.md").write_text(md, encoding="utf-8")

    print(f"Wrote {len(entries)} bundles to {content}")
    if missing_img:
        print(f"WARNING: {len(missing_img)} bundles have no image yet: "
              + ", ".join(missing_img[:10]) + ("…" if len(missing_img) > 10 else ""))
    return 0


if __name__ == "__main__":
    raise SystemExit(main())